Can you dodge some psychic powers like fire bolt (175) or if the psycker makes their rolls they hit regardless?

As long as they make an attack roll of any kind you can use your reaction to dodge it.

Cool! Then we did it right.. and thank the Emeror for that because that POS traitor alcolyte would have cooked my goose if I was not able to dodge!

Thanks!

I also allowed to dodge powers like firestorm. Just treat them as dodging blast weapons, with blast equal to power radius.